Introduction
Calcareous soils are those where calcium carbonate (either soft carbonate fractions or limestone) is an important part of the soil composition within at least some layers of the soil profile. These soils are widespread in south-eastern Australia but within the agricultural zone are most common in low rainfall areas. The upper Eyre Peninsula (EP) is an agricultural region where calcareous soils, including some that are extremely high in carbonate throughout the profile, dominate the landscape. Despite calcareous soils being most common in drier environments, they are also important soils in areas such as the South-East and Yorke Peninsula (YP) of South Australia (SA) as well as other parts of Australia.
The nature of calcareous soils results in many constraints to agricultural productivity and while these constraints may not be unique to calcareous soils, they are often most extreme in these soils. Rhizoctonia root rot, boron toxicity and phosphorus deficiency are just three issues that can be both severe and widespread in crops and pastures grown in calcareous soils, especially in highly calcareous soils.
The purpose of this review is to summarise the following:
- Where calcareous soils occur within the agricultural zone of southern Australia with emphasis on the upper EP and South-East regions of SA.
- The types of farming systems practised on them, how their productivity rates in terms of their water-limited potential, and how much of any productivity gaps are due to the properties of their calcareous soils. The major focus will be on highly calcareous soils because they tend to manifest these constraints most severely.
- Local research already conducted into constraints posed by calcareous soils.
- Gaps that exist in that knowledge, and opportunities for improved productivity for farming systems on calcareous soils.
This document is an early step in the delivery of a research initiative that will identify the impacts of topsoil and subsoil chemical conditions of highly calcareous soils on crop productivity on the upper Eyre Peninsula and in the South-East of South Australia. Integrated solutions to reduce the impact of these multiple constraints to cropping will then be developed.
Citation: Wilhelm, N, Dzoma, B, Evans, M, Masters, B, Gupta, V, McBeath, T, Van Zwieten, L, Tavakkoli, E (2021). Literature Review: The nature of highly calcareous soils and their impact on crop productivity (4.2.003). Cooperative Research Centre for High Performance Soils, Callaghan, NSW.
Read the full literature review.
This literature review is part of the Soil CRC’s research project, ‘Overcoming soil constraints in highly calcareous soils‘ (4.2.003). See the related resources on this page for more information.